Enhancing fault management performance of two-step QoS routing algorithms in GMPLS networks

In this paper a novel methodology aimed at minimizing the probability of network failure and the failure impact (in terms of QoS degradation) while optimizing the resource consumption is introduced. A detailed study of MPLS recovery techniques and their GMPLS extensions are also presented. In this scenario, some features for reducing the failure impact and offering minimum failure probabilities at the same time are also analyzed. Novel two-step routing algorithms using this methodology are proposed. Results show that these methods offer high protection levels with optimal resource consumption

Enhancing MPLS QoS routing algorithms by using the network protection degree paradigm

IP based networks still do not have the required degree of reliability required by new multimedia services, achieving such reliability will be crucial in the success or failure of the new Internet generation. Most of existing schemes for QoS routing do not take into consideration parameters concerning the quality of the protection, such as packet loss or restoration time. In this paper, we define a new paradigm to develop new protection strategies for building reliable MPLS networks, based on what we have called the network protection degree (NPD). This NPD consists of an a priori evaluation, the failure sensibility degree (FSD), which provides the failure probability and an a posteriori evaluation, the failure impact degree (FID), to determine the impact on the network in case of failure. Having mathematical formulated these components, we point out the most relevant components. Experimental results demonstrate the benefits of the utilization of the NPD, when used to enhance some current QoS routing algorithms to offer a certain degree of protection

Multicast algorithms evaluation using an adaptative routing in ATM networks

This paper proposes a multicast implementation based on adaptive routing with anticipated calculation. Three different cost measures for a point-to-multipoint connection: bandwidth cost, connection establishment cost and switching cost can be considered. The application of the method based on pre-evaluated routing tables makes possible the reduction of bandwidth cost and connection establishment cost individually

Improving Clustering Algorithms for Image Segmentation using Contour and Region Information

In image segmentation, clustering algorithms are very popular because they are intuitive and, some of them, easy to implement. For instance, the k-means is one of the most used in the literature, and many authors successfully compare their new proposal with the results achieved by the k-means. However, it is well known that clustering image segmentation has many problems. For instance, the number of regions of the image has to be known a priori, as well as different initial seed placement (initial clusters) could produce different segmentation results. Most of these algorithms could be slightly improved by considering the coordinates of the image as features in the clustering process (to take spatial region information into account). In this paper we propose a significant improvement of clustering algorithms for image segmentation. The method is qualitatively and quantitative evaluated over a set of synthetic and real images, and compared with classical clustering approaches. Results demonstrate the validity of this new approach

Integración de SEXTANTE en GearSCape

SEXTANTE es un marco para el desarrollo de algoritmos dedicados al procesamiento de información geográficamente referenciada, que actualmente cuenta con más de doscientos algoritmos que son capaces de operar sobre datos vectoriales, alfanuméricos y raster. Por otra parte, GearScape es un sistema de información geográfico orientado al geoprocesamiento, que dispone de un lenguaje declarativo que permite el desarrollo de geoprocesos sin necesidad de herramientas de desarrollo complejas. Dicho lenguaje está basado en el estándar SQL y extendido mediante la norma OGC para el acceso a fenómenos simples. Al ser un lenguaje mucho más simple que los lenguajes de programación imperativos (java, .net, python, etc.) la creación de geoprocesos es también más simple, más fácil de documentar, menos propensa a bugs y además la ejecución es optimizada de manera automática mediante el uso de índices y otras técnicas. La posibilidad de describir cadenas de operaciones complejas tiene también valor a modo de documentación: es posible escribir todos los pasos para la resolución de un determinado problema y poder recuperarlo tiempo después, reutilizarlo fácilmente, comunicárselo a otra persona, etc. En definitiva, el lenguaje de geoprocesamiento de GearScape permite "hablar" de geoprocesos. La integración de SEXTANTE en GearScape tiene un doble objetivo. Por una parte se pretende proporcionar la posibilidad de usar cualquiera de los algoritmos con la interfaz habitual de SEXTANTE. Por la otra, se pretende añadir al lenguaje de geoprocesamiento de GearScape la posibilidad de utilizar algoritmos de SEXTANTE. De esta manera, cualquier problema que se resuelva mediante la utilización de varios de estos algoritmes puede ser descrito con el lenguaje de geoprocesamiento de GearScape. A las ventajas del lenguaje de GearScape para la definición de geoprocesos, se añade el abanico de geoprocesos disponible en SEXTANTE, por lo que el lenguaje de geoprocesamiento de GearScape nos permite "hablar" utilizando vocabulario de SEXTANTE

Integration of knowledge-based, qualitative and numeric tools for real time dynamic systems supervision

The proposal presented in this thesis is to provide designers of knowledge based supervisory systems of dynamic systems with a framework to facilitate their tasks avoiding interface problems among tools, data flow and management. The approach is thought to be useful to both control and process engineers in assisting their tasks. The use of AI technologies to diagnose and perform control loops and, of course, assist process supervisory tasks such as fault detection and diagnose, are in the scope of this work. Special effort has been put in integration of tools for assisting expert supervisory systems design. With this aim the experience of Computer Aided Control Systems Design (CACSD) frameworks have been analysed and used to design a Computer Aided Supervisory Systems (CASSD) framework. In this sense, some basic facilities are required to be available in this proposed framework: ·